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2.
Zhonghua Er Ke Za Zhi ; 60(10): 1045-1053, 2022 Oct 02.
Artigo em Chinês | MEDLINE | ID: mdl-36207852

RESUMO

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum ß-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ2=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.


Assuntos
Abscesso Encefálico , Hidrocefalia , Meningites Bacterianas , Derrame Subdural , Adolescente , Criança , Pré-Escolar , Escherichia coli , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/epidemiologia , Estudos Retrospectivos , Streptococcus agalactiae , Streptococcus pneumoniae , beta-Lactamases
4.
Neoplasma ; 67(5): 1139-1145, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32412773

RESUMO

Beta-glucosidase (GBA), also known as acid ß-glucosidase, exhibits an activity of glucosylceramidase (EC 3.2.1.45). Three main isoforms of ß-glucosidases have been identified in mammals: GBA1, GBA2, and GBA3. The deficiency of these enzymes leads to glucosylceramide accumulation, resulting in Gaucher's disease. The present study is focused on the cytosolic ß-glucosidase, GBA3, and its relationship with hepatocellular carcinoma (HCC). The expression of GBA3 mRNA in HCC was evaluated first using the TCGA database, and then by immunohistochemistry using tissue microarrays of 328 clinically characterized HCC samples and 151 non-tumor liver controls. Moreover, the presence of a correlation between GBA3 expression and clinicopathological characteristics of patients was examined. The obtained results indicated that the expression of GBA3 mRNA was significantly lower in HCC than in the adjacent non-tumor liver tissues. The expression of GBA3 was inversely related to the number of tumors (p=0.041), tumor size (p<0.001), Edmondson grade (p=0.007), microvascular invasion (p=0.049), patient status (p<0.001), and α-fetoprotein level (p<0.001). Patients exhibiting low GBA3 expression had a shorter survival time than those with high expression (p<0.001). In conclusion, the decreased GBA3 expression is strongly associated with a poor prognosis in HCC patients, and GBA3 may be a potential therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , beta-Glucosidase/genética , Biomarcadores Tumorais , Carcinoma Hepatocelular/diagnóstico , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/diagnóstico , Prognóstico
7.
Eur Rev Med Pharmacol Sci ; 23(7): 3021-3033, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31002153

RESUMO

OBJECTIVE: Cardiomyocyte hypertrophy is considered to be a compensatory process of heart suffering from pathological damages. This study aimed to evaluate effects of Na+/K+ APTaseα2 (NAKα2) on isoprenaline (ISO) induced cardiomyocyte hypertrophy. MATERIALS AND METHODS: Mouse atrial cardiomyocytes were cultured and treated with ISO to establish cardiomyocyte hypertrophy model. NAKα2 over-expression and small interfere RNA (siRNA) plasmids were constructed and transfected to cardiomyocytes. Influx Ca2+ ([Ca2+]i) was measured using flow cytometry method. Fibrosis formation was examined with Masson staining. Transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) staining was used to examine apoptosis. Major histocompatibility complex ß (ß-MHC), atrial natriuretic peptides (ANP), B-type natriuretic peptides (BNP) were evaluated with quantitative Real-time PCR (qRT-PCR). Western blot was used to detect ß-MHC, ANP, BNP, Na+/Ca2+ exchanger (NCX) and L-type calcium channel (LTCC). RESULTS: NAKα2 significantly inhibited NCX and LTCC expression compared to that in ISO-treated cardiomyocytes (p<0.05). NAKα2 significantly suppressed expression of ß-MHC, ANP and BNP compared to that in ISO-treated cardiomyocytes (p<0.05). NAKα2 significantly alleviated fibrosis formation and inhibited apoptosis compared to that in ISO-treated cardiomyocytes (p<0.05). NAKα2 reduced intracellular calcineurin and activated phosphorylation of calcineurin-nuclear factor of activated T cells (NFAT) compared to ISO-treated cardiomyocytes (p<0.05). NAKα2 significantly strengthened effects of Klotho on ISO-induced up-regulation of hypertrophy associated molecules (p<0.05) by activating LTCC and NCX. Comparing to ISO-treated cardiomyocytes, NAKα2 combining Klotho treatment exhibited significantly better improvement of Ca2+ influx, alleviation of fibrosis and reduction of apoptosis by triggering LTCC/NCX signaling pathway. CONCLUSIONS: Over-expression of NKAα2 suppressed fibrosis formation and protected against cardiomyocyte hypertrophy by inhibiting hypertrophy associated molecules, alleviating apoptosis and activating LTCC/NCX signaling pathway.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Cardiomegalia/metabolismo , Miócitos Cardíacos/metabolismo , Transdução de Sinais/fisiologia , Trocador de Sódio e Cálcio/metabolismo , ATPase Trocadora de Sódio-Potássio/biossíntese , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Linhagem Celular , Fibrose/genética , Fibrose/metabolismo , Fibrose/patologia , Camundongos , Miócitos Cardíacos/patologia , ATPase Trocadora de Sódio-Potássio/genética
8.
Pol J Vet Sci ; 21(2): 371-376, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30450877

RESUMO

Self-biting disease occurs in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis (BSA) in combination with RAPD method to analyze a molecular genetic marker linked with self-biting trait in mink group. The molecular marker was converted into SCAR and loop-mediated isothermal amplification (LAMP) marker for rapid detection of this disease. A single RAPD marker A10 amplified a specific band of 1000bp in self-biting minks. The sequences of the bands exhibited 73% similarity to the Canis Brucella. SCAR and LAMP marker were designed for the specific fragment of RAPD marker A10 and validated in 30 self-biting minks and 30 healthy minks. c2 test showed difference (p0.05) with SCAR and significant difference (p0.01) with LAMP in the detection rate between the two groups, but LAMP method was more accurate than SCAR method. This indicated that LAMP can be used as a positive marker to detect self-biting disease in minks.


Assuntos
Mordeduras e Picadas , Vison , Técnicas de Amplificação de Ácido Nucleico , Técnica de Amplificação ao Acaso de DNA Polimórfico , Agricultura , Animais , Comportamento Animal , Mordeduras e Picadas/veterinária , Brucella/genética , Sensibilidade e Especificidade
10.
Immunol Invest ; 44(6): 521-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26207789

RESUMO

Total glucoside of paeony (TGP), extracted from the root of Paeonia Lactiflora, has been known to show anti-inflammatory, anti-oxidative, hepato-protective and immuno-regulatory activities. The aim of this present study was to determine the anti-tumor effect of TGP against N-nitrosodiethylamine (DEN)-induced hepatocellular carcinoma (HCC) in rats, and to find the related mechanisms. Rat HCC model was established by intragastrically administrating with DEN (8 mg/kg). We found the number of tumor nodules and the index of liver and spleen were increased in the model group compared with the normal group, and was significantly decreased by TGP. Additionally, TGP obviously improved the hepatic pathological lesions induced by DEN, and decreased the elevated levels of serum alanine aminotransferase (ALT), glutamic oxalacetic transaminase (AST), alkaline phosphatase (ALP) and alpha fetoprotein (AFP) by DEN. Moreover, TGP decreased the level of B cell-activating factor (BAFF) and the proportion of IL-10-producing regulatory B cells (Bregs), and the decrease of BAFF by TGP is positively correlated to the decrease of IL-10-producing Bregs by TGP. These results suggest that TGP had a good therapeutic action on DEN-induced HCC rats, which might be due to its down-regulation of Bregs through reducing the level of BAFF.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Linfócitos B Reguladores/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Glucosídeos/uso terapêutico , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Paeonia , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Antineoplásicos Fitogênicos/farmacologia , Aspartato Aminotransferases/sangue , Fator Ativador de Células B/sangue , Linfócitos B Reguladores/imunologia , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Dietilnitrosamina , Regulação para Baixo , Glucosídeos/farmacologia , Interleucina-10/imunologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/imunologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Fitoterapia , Ratos Sprague-Dawley
11.
Oncogene ; 34(34): 4471-81, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25435373

RESUMO

Dysregulation of ribosome biogenesis or translation can promote cancer, but the underlying mechanisms remain unclear. UTP18 is a component of the small subunit processome, a nucleolar multi-protein complex whose only known function is to cleave pre-ribosomal RNA to yield the 18S ribosomal RNA component of 40S ribosomal subunits. Here, we show that UTP18 also alters translation to promote stress resistance and growth, and that UTP18 is frequently gained and overexpressed in cancer. We observed that UTP18 localizes to the cytoplasm in a subset of cells, and that serum withdrawal increases cytoplasmic UTP18 localization. Cytoplasmic UTP18 associates with the translation complex and Hsp90 to upregulate the translation of IRES-containing transcripts such as HIF1a, Myc and VEGF, thereby inducing stress resistance. Hsp90 inhibition decreases cytoplasmic UTP18 and UTP18-induced increases in translation. Importantly, elevated UTP18 expression correlates with increased aggressiveness and decreased survival in numerous cancers. Enforced UTP18 overexpression promotes transformation and tumorigenesis, whereas UTP18 knockdown inhibits these processes. This stress adaptation mechanism is thus co-opted for growth by cancers, and its inhibition may represent a promising new therapeutic target.


Assuntos
Neoplasias/etiologia , Proteínas Nucleares/fisiologia , Biossíntese de Proteínas , RNA Ribossômico 18S/metabolismo , Subunidades Ribossômicas Menores de Eucariotos/metabolismo , Animais , Linhagem Celular Tumoral , Nucléolo Celular/metabolismo , Transformação Celular Neoplásica , Citoplasma/metabolismo , Proteínas de Choque Térmico HSP90/fisiologia , Humanos , Masculino , Camundongos , Neoplasias/genética , Subunidades Proteicas
12.
Bratisl Lek Listy ; 115(7): 427-33, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25077366

RESUMO

OBJECTIVE: Evidence suggests that paeoniflorin may be involved in anticancer activities. Here, we have investigated the effects of paeoniflorin and correlative mechanisms on anti-invasion and anti-metastasis in human hepatocellular carcinoma (HCC) cell lines. MATERIALS AND METHODS: In the current study, we have applied 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay to determine the proliferative effect of HepG2 and Bel-7402, two human hepatoma cell lines, and we have established a boyden chamber assay, a wound healing assay and cell adhesion assay to detect and quantify the invasion, metastasis and adhesion of both HepG2 and Bel-7402. In addition, we have analyzed the protein expression of matrix metalloproteinas (MMP)-9, E-cadherin (E-cad) and extracellular signal-regulated kinase (ERK) in both cell lines through western blot analysis. RESULTS: Paeoniflorin (6. 25-200 µM) had inhibitory effect on the growth of HepG2 and Bel-7402 cell lines, and reduced significantly invasion, metastasis and adhesion of HCC cell lines. In addition, paeoniflorin decreased the expression of MMP-9 and ERK in HepG2 and Bel-7402 cells, and increased expression of E-cad in both cell lines. CONCLUSIONS: Paeoniflorin is effective anti-metastatic and anti-invasive agent for suppressing HCC invasion and metastasis (Fig. 5, Ref. 30).


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Glucosídeos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Monoterpenos/uso terapêutico , Caderinas/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/secundário , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Imunoglobulina G/farmacologia , Neoplasias Hepáticas/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Melfalan/farmacologia , Invasividade Neoplásica/patologia , Invasividade Neoplásica/fisiopatologia , Invasividade Neoplásica/prevenção & controle , Paeonia , Fosfotransferases/metabolismo , Fitoterapia , Preparações de Plantas/farmacologia , Células Tumorais Cultivadas
13.
Cell Death Dis ; 4: e905, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24201804

RESUMO

Tumor multidrug resistance (MDR) can result from overexpression of drug transporters and deregulation of cellular signaling transduction. New agents and strategies are required for overcoming MDR. Here, we report that tanshinone-1, a bioactive ingredient in traditional Chinese medicine, directly killed MDR tumor cells and their corresponding parental cells, which was potentiated by inhibition of secondary activation of signaling networks. Tanshinone-1 was slightly more potent at inducing cytotoxicity and apoptosis in MDR cells than in corresponding parental cells. Tanshinone-1-induced MDR cell killing was independent of the function and expression of drug transporters but was partially correlated with the phosphatase-dependent reduction of phospho-705-Stat3, which secondarily activated p38-, AKT-, and ERK-involved signaling networks. Cotreatments with p38, AKT, and ERK inhibitors potentiated the anti-MDR effects of tanshinone-1. Our study presents a model for MDR cell killing using a compound of natural origin. This model could lead to new therapeutic strategies for targeting signaling network(s) in MDR cancers as well as new strategies for multitarget design.


Assuntos
Abietanos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Citometria de Fluxo , Humanos , Camundongos , Células NIH 3T3 , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
AJNR Am J Neuroradiol ; 34(10): 1901-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23449656

RESUMO

BACKGROUND AND PURPOSE: In the clinical setting, there is a need to perform mismatch measurements quickly and easily on the MR imaging scanner to determine the specific amount of treatable penumbra. The objective of this study was to quantify the agreement of the ABC/2 method with the established planimetric method. MATERIALS AND METHODS: Patients (n = 193) were selected from the NINDS Natural History Stroke Registry if they 1) were treated with standard intravenous rtPA, 2) had a pretreatment MR imaging with evaluable DWI and PWI, and 3) had an acute ischemic stroke lesion. A rater placed the linear diameters to measure the largest DWI and MTT lesion areas in 3 perpendicular axes-A, B, and C-and then used the ABC/2 formula to calculate lesion volumes. A separate rater measured the planimetric volumes. Multiple mismatch thresholds were used, including MTT volume - DWI volume ≥50 mL versus ≥60 mL and (MTT volume - DWI volume)/MTT volume ≥20% versus MTT/DWI = 1.8. RESULTS: Compared with the planimetric method, the ABC/2 method had high sensitivity (0.91), specificity (0.90), accuracy (0.91), PPV (0.90), and NPV (0.91) to quantify mismatch by use of the ≥50 mL definition. The Spearman correlation coefficients were 0.846 and 0.876, respectively, for the DWI and MTT measurements. The inter-rater Bland-Altman plots demonstrated 95%, 95%, and 97% agreement for the DWI, MTT, and mismatch measurements. CONCLUSIONS: The ABC/2 method is highly reliable and accurate for quantifying the specific amount of MR imaging-determined mismatch and therefore is a potential tool to quickly calculate a treatable mismatch pattern.


Assuntos
Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Acidente Vascular Cerebral/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Recuperação de Função Fisiológica , Sistema de Registros , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico
15.
Inflamm Res ; 61(11): 1229-39, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22802109

RESUMO

OBJECTIVE: To further explore the mechanism of etanercept (ENT, rhTNFR:Fc) and methotrexate (MTX) in the combined treatment of rheumatoid arthritis (RA), we investigated whether thymic and splenic T-cell subsets and their related cytokines imbalance could be restored by ETN/MTX treatment. METHODS: The effect of ETN/MTX on collagen-induced arthritis (CIA) was evaluated by arthritis scores, joint and spleen histopathology, as well as indices of thymus and spleen. T lymphocytes proliferation was determined by [(3)H]-TdR incorporation. Levels of TNF-α, LT-α, IL-1ß, RANKL, IL-10, IL-17, IFN-γ and IL-6 were detected by enzyme linked immunosorbent assay. The subsets of T lymphocytes including CD4(+), CD8(+), CD3(+)CD4(+), CD4(+)CD25(+), CD4(+)CD62L(+) and CD4(+)CD25(+)Foxp3(+) cells were quantified using flow cytometry. RESULTS: Combined administration of ETN/MTX significantly inhibited the proliferation of T lymphocytes, decreased serum IL-6, TNF-α, IL-1ß, RANKL and macrophage supernatant IL-17, LT-α, increased serum IFN-γ and macrophage supernatant IL-10. Moreover, the combined administration could restore CD4(+)/CD8(+) ratio and Treg cells of CIA thymus and spleen. CONCLUSION: Taken together, our findings suggest that ENT/MTX may modify the abnormal T lymphocytes balance from central to peripheral lymphoid organs, which may partially, explained the mechanism of the combined administration.


Assuntos
Antirreumáticos/administração & dosagem , Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Imunoglobulina G/administração & dosagem , Metotrexato/administração & dosagem , Receptores do Fator de Necrose Tumoral/administração & dosagem , Animais , Artrite Experimental/sangue , Artrite Experimental/patologia , Artrite Reumatoide/sangue , Artrite Reumatoide/patologia , Relação CD4-CD8 , Citocinas/sangue , Etanercepte , Masculino , Camundongos , Camundongos Endogâmicos DBA , Ligante RANK/sangue , Baço/efeitos dos fármacos , Baço/imunologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Timo/efeitos dos fármacos , Timo/imunologia
16.
J Asian Nat Prod Res ; 9(2): 175-82, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17454315

RESUMO

A new triterpenoid saponin, named stauntoside A (1) along with four known saponins (2,3,4,5) was isolated from Stauntonia chinensis DC., (Lardizabalaceae). Their structures were elucidated by spectroscopic analysis and chemical methods as 3-O-alpha-L-arabinopyranosyl-30-norhederagenin -28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (1), 3-O-alpha-L-arabinopyranosyl-30- norhederagenin-28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (2), 3-O-alpha-L-rhamnopyranosyl-(1 --> 2)-alpha-L-arabinopyranosyl-30-norhederagenin-28-O-alpha-L- rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (3), 3-O-alpha-L- arabinopyranosyl-hederagenin-28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D- glucopyranosyl ester (4), 3-O-alpha-L-rhamnopyranosyl-(1 --> 2)-alpha-L-arabinopyranosyl-hederagenin -28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (5). The (1)H and (13)C NMR data for Glycoside L-G1 or Sinofoside A are paradox in the reported before. Thus, the structure elucidation of saponin 2, known as Glycoside L-G1 or Sinofoside A, was discussed and the unambiguous assignments were given.


Assuntos
Magnoliopsida/química , Saponinas/isolamento & purificação , Esteroides/isolamento & purificação , Estrutura Molecular , Saponinas/química , Esteroides/química
17.
Eur J Biochem ; 266(3): 778-88, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10583371

RESUMO

An agglutinin that has high affinity for GalNAcbeta1-->, was isolated from seeds of Wistaria sinensis by adsorption to immobilized mild acid-treated hog gastric mucin on Sepharose 4B matrix and elution with aqueous 0.2 M lactose. The binding property of this lectin was characterized by quantitative precipitin assay (QPA) and by inhibition of biotinylated lectin-glycan interaction. Of the 37 glycoforms tested by QPA, this agglutinin reacted best with a GalNAcbeta1-->4 containing glycoprotein (GP) [Tamm-Horsfall Sd(a+) GP]; a Galbeta1-->4GlcNAc containing GP (human blood group precursor glycoprotein from ovarian cyst fluid and asialo human alpha1-acid GP) and a GalNAcalpha1-->3GalNAc containing GP (asialo bird nest GP), but poorly or not at all with most sialic acid containing glycoproteins. Among the oligosaccharides tested, GalNAcalpha1-->3GalNAcbeta1-->3Galalpha1-->4Galbeta 1-->4Glc (Fp) was the most active ligand. It was as active as GalNAc and two to 11 times more active than Tn cluster mixtures, Galbeta1--> 3/4GlcNAc (I/II), GalNAcalpha1-->3(L-Fucalpha1-->2)Gal (Ah), Galbeta1-->4Glc (L), Galbeta1-->3GalNAc (T) and Galalpha1--> 3Galalpha-->methyl (B). Of the monosaccharides and their glycosides tested, p-nitrophenyl betaGalNAc was the best inhibitor; it was approximately 1.7 and 2.5 times more potent than its corresponding alpha anomer and GalNAc (or Fp), respectively. GalNAc was 53.3 times more active than Gal. From the present observations, it can be concluded that the Wistaria agglutinin (WSA) binds to the C-3, C-4 and C-6 positions of GalNAc and Gal residues; the N-acetyl group at C-2 enhances its binding dramatically. The combining site of WSA for GalNAc related ligands is most likely of a shallow type, able to recognize both alpha and beta anomers of GalNAc. Gal ligands must be Galbeta1-->3/4GlcNAc related, in which subterminal beta1-->3/4 GlcNAc contributes significantly to binding; hydrophobicity is important for binding of the beta anomer of Gal. The decreasing order of the affinity of WSA for mammalian structural carbohydrate units is Fp >/= multi-II > monomeric II >/= Tn, I and Ah >/= E and L > T > Gal.


Assuntos
Lectinas/isolamento & purificação , Magnoliopsida/química , Animais , Sítios de Ligação , Sequência de Carboidratos , Feminino , Glicoproteínas/química , Glicoproteínas/metabolismo , Testes de Hemaglutinação , Humanos , Técnicas In Vitro , Lectinas/química , Lectinas/metabolismo , Dados de Sequência Molecular , Lectinas de Plantas , Sementes/química
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